I cant rember who posted this link (was it Kestas?) but I found it interesting enough to bookmark.
http://www.robertstanley.biz/firestorm.htm
This might be a little off the topic of this thread (not directly related to platinums vs coppers...) but I thought it might be a good place to get some feed back on it and get it a little exposure.
Edit: So as to actually contribute to the point of the thread... If you run coppers (at about ¼ the price) you could change them more often and have cleaner plugs and less siezed threads... though the right amount of anti sieze prevents that as well.